Two former senators threw their energy policy weight Tuesday to make the case that the private sector — rather than federal government — should decide whether to export natural gas.

“Markets are dynamic. There are many factors [that] are working [that] change by the month. Some change daily,” former Sen. J. Bennett Johnston (D-La.) told lawmakers on a House Energy and Commerce Committee subpanel, citing fluctuating expenses like labor rates, interest rates and fuel costs.

“The market’s not perfect,” he added, “but I think it’s better than what the regulators would be.”

Johnston chaired the Senate Energy and Natural Resources Committee from 1987 to 1995 and is now chairman of Johnston & Associates.

The hearing came as the Energy Department is reviewing several applications by companies that want to export liquefied natural gas — a sharp turnaround from just a few years ago, when U.S. gas supplies seemed limited.

Former Sen. Byron Dorgan (D-N.D.), sitting at the witness table beside Johnston, told the committee that the last time he was in the same Rayburn hearing room was in 2007, when the Federal Energy Regulatory Commission “said we were running out of natural gas.” FERC reviews proposals to build LNG terminals and regulates interstate natural gas pipelines.

“We believe the market should make the decision about the exports of natural gas,” said Dorgan, who’s now a co-chairman of the Bipartisan Policy Center’s Energy Project. He was also rumored to be on President Barack Obama’s shortlist of candidates for energy secretary before the president tapped Ernest Moniz.

Dorgan said U.S. natural gas exports to Canada and Mexico have doubled since 2007, a fact backed up by data from the Energy Information Administration.

“I think it’s far more likely that domestic prices will affect exports than it is that exports will affect domestic prices,” Dorgan said, addressing critics’ warnings that increased exports will drive up gas prices for U.S. consumers and manufacturers.

The export question also raises geopolitical issues.

Amy Jaffe, director of energy and sustainability at the University of California-Davis, told lawmakers that LNG exports could help limit Russia’s ability to use its large energy supplies to split the U.S. and its European allies. She also said that because free trade is so ingrained in U.S. foreign policy, “we cannot ourselves then have a policy where we choose to restrict our exports.”

“Because therefore, we move into a world where energy becomes possibly a political weapon or an economic weapon and that is not in the vital interests of the U.S.,” Jaffe said.

“For these young folks on the second row here in front of me, there’s hope,” Rep. Joe Barton (R-Texas) said. “We might actually burst out in bipartisanship on LNG exports.”

Rep. Henry Waxman, the top Democrat on the Energy and Commerce Committee, said he views the whole issue of natural gas “from the perspective of climate change.” But on LNG exports, he said, “I’m open to that issue. I want to think about it.”

So far, the Department of Energy has approved just one application to export LNG to a country that doesn’t have a free-trade agreement with the U.S. That approval was for Cheniere Energy’s Sabine Pass project, which is expected to begin exporting in 2015 or 2016. Nineteen more applications are pending.

Applications for LNG exports to the 18 countries that have free-trade agreements with the U.S. must be automatically approved. So far, DOE has granted 23 of those for shipments that could total as much as 29.41 billion cubic feet per day from 19 planned liquefaction facilities.

But for countries without those trade agreements, DOE must decide whether granting the request is in the public interest.

Some lawmakers, including Senate Energy Chairman Ron Wyden (D-Ore.), are wary of exporting abundant gas made accessible through hydraulic fracturing. Last month, Wyden said he supported exporting most products but was hesitant to do the same with energy.

“Energy is not blueberries,” he said at the time. “Let’s make sure that we look before we leap.”

Despite his uneasiness, Wyden and Energy Committee ranking member Lisa Murkowski of Alaska have begun lining up a series of natural gas forums for their panel.

Obama stoked the hopes of gas-export supporters last weekend with his remarks at an economic development forum in Costa Rica, where he noted that “we are likely to be a net natural gas exporter as soon as 2020.”

“I’ve got to make a decision — an executive decision broadly about whether or not we export liquefied natural gas at all,” Obama said. “But I can assure you that once I make that decision, then factoring in how we can use that to facilitate lower costs in the hemisphere and in Central America will be on my agenda.”

On the opposition side, Dow Chemical earlier this year formed a group with steel-maker Nucor and aluminum giant Alcoa that rejects unfettered natural gas exports.

The uncertainties in gas supply and demand are too great to allow all the applications before DOE to go forward, George Biltz, Dow’s vice president for energy and climate issues, said when the group first formed. He said approving all the export applications before DOE would create a “laissez-faire” economic policy rather than an orderly free-market system.